1. Technical Field
Exemplary embodiments of the present disclosure are directed to a lens module and a display apparatus having the lens module. More particularly, exemplary embodiments of the present disclosure are directed to a lens module for a display apparatus that can display a 3-dimensional (3D) stereoscopic image and a display apparatus having the lens module.
2. Description of the Related Art
In general, a display apparatus displays a 2-dimensional (2D) image. Recently, due to increased demand for 3-dimensional (3D) stereoscopic images for films, games, etc., stereoscopic image display apparatuses have been developed that can display a 3D stereoscopic image.
A 3D stereoscopic image may be displayed by exploiting the binocular parallax of both eyes. Methods of displaying a 3D stereoscopic image may be classified as either shutter-glasses type methods or auto-stereoscopic type methods. Auto-stereoscopic type methods include barrier type methods, lenticular type methods, liquid crystal lens type methods, etc.
A lenticular type method uses a convex lens or a Fresnel lens. A Fresnel lens is thinner than a convex lens. A Fresnel lens has a plurality of circular arcs on its surface and refracts light through the circular arcs thereof.
Liquid crystal directors may be controlled by an electric field, from which a liquid crystal lens may be fabricated. A liquid crystal lens includes an upper substrate, a lower substrate and a liquid crystal layer between the upper substrate and the lower substrate. A liquid crystal director having a liquid crystal layer may be challenging to control, and may have a slow response time with respect to mode changes. Thus, a display apparatus having a liquid crystal lens may be slow in switching between a 2D mode and a 3D mode.